Cut-off valve



(No Model.) f 2 Sheets-Sheet 1.

. J. W. MBLVIN.

yGUT-OPP VALVE.

N0. 543,259. vPazented July 23, 1895.

(No Model.) 2 Sheets-Sheet 2.

J. W. MELVIN.

l UNITED STATES PATENT OFFICE.

JOSIAH W. MELVIN, OF HOUSTON, TEXAS.

CUT-O FF VALVE.

SPECIFICATION forming part of Letters Patent No. 543,259,01ated July 23,1 895.

Application iiled March 23, 1895.

To all whom it may concern.:

` a specification.

f to

This invention relates to shut-olf valves having valve-plugs mechanically actuated by rotary valve-stems provided with cranks or eccentric pins which loosely engage the valveplugs and serve to shift the latter longitudinally to or from the valve-seats when the stems are rotated.

The objects of my invention are to improve the prior construction of valves of the character alluded to; to provide a novel valveplug, which can be provided with either a rigid or Iiexible valve-face, according to the purpose for which the valve is to be used; to provide novel means for rectilinearly guiding the Y valve -plug and preventing axially turning movements of the same which might interfere with its correct operative connection with the crank or eccentric pin of the valve-stem; to provide a novel arrangement of spring to aid in seating the valve plug and holding it tightly against the valve seat; to provide means for pressing the valve-stem upwardly and seating a flange thereupon against a nut screwed into the valve-casing; to prevent the passage of liquid or iiuid at this point, and thus avoid leakage throughthat part of the valve-casing which contains the valve-stem, and to provide a novel construction of valvecasing whereby the valve-plug is accurately centered and supportedby bearing against the internal surface of the easing nearly its entire circumference, while the passages for the iiuid from the inlet to the outlet of the casing are wholly beneath the valve-plug.

To accomplish all these objects my inven tion'involves the features of construction and the combination or arrangement of parts hereinafter described and claimed, reference being made tothe accompanying drawings, in

whichr Figure 1 is a Vertical central sectional view of my improved shut-oftvalve, the valve-stem and valve-plug being shown in side elevation. Fig. 2 is a sectional rear end elevation of the Y same. Fig. 3 is a detail perspective view of Serial No. 542,948. (No model.)

.which is particularly designed for application to a steam-conveying pipe.

In order to enable those skilled in the art to make and use my invention, l will now describe the same in detail, referring to the drawings, Wherein- The numeral 1 indicates a Valve-casing having an internal screw-threaded inlet extremity 2,acurved internally-screw-threaded or other suitable outlet extremity 3, and an upwardlyprojecting tubular portion 4 for containing the cylindrical valve-stem 5 hereinafter explained. The casing is constructed internally with a circular radially-projecting flange 6, the inner edge of whichconstitutes a Valveseat 7, and said' casing is formed integral in its lower portion with a plurality of upwardly- 4projecting ribs 8, 9, and 10, separated from one anotherl a suitable distance to provide longitudinal water-passages 12 and 13 under the lower side of the cylindrical. valve-plug 14. The inner or upper edges of the ribs '8, 9, and lOare concentric with the center ot' the cylindrical valve-plug 14, and serve to solely sustain the valve-plug in its rectilinear reciprocation motion. The central rib 9 extends into the space between two parallel guide flanges or ribs 15, formed onl the under side of the cylindrical valve-plug, so that the latter is accurately guided in'a right line in the direction of its length, and is held against axially-turning movements. The upper side of the valve-plug bears against the internal cylindrical surface 'of the valve-casing, and

per edges of the ribs 8, 9, and 10. The valvecasing is also formed with water-passages 16 and 17, located, respectively, above the ribs 8 and 10, so that when the valve-plug is opened the water will flow longitudinally through the water-passages 12, 13, 16, and 17 into the outvthe valveplug may also bear against the uplet ot the Valve-casing.

The valve-plug is constructed in-its upper sidewith a transverse slot 18, in which is ar- ICO ranged a cylindrical crank or eccentric pin 19, projecting from the lower end of the valvestem 5. The valve-stem is formed integrally,

or is otherwise provided with an annular ange 20, having a beveled or inclined upper surface, seated upon a beveled or inclined seat 21, formed on the lower end of a nut 22, screwed into the upper end of the portion 4, and through which the Valve-stem extends. In the lower part of the portion 4 is arranged a washer 23, which serves as a bearing for the lower end of a spiral or other suitable spring 24, resting at its upper end against the flange 20, so thatthe latter is constantly pressed upward and tightly seated upon the seat 21 of thenut 22 to prevent the passageof liquid or fluid at such point, and thus avoid leakage through that part of the valve-casing which contains the valve-stem. The upper end of the valve-stem is suitably constructed to receive a handle by which to rotate the stern, and thus shift the valve-plug 14 longitudinally to or from the valve-seat 7. I prefer to Vconstruct the upper end of the valve-stem with an angular head 25 to receive a crankhandle, but do not confine myself to this par ticular construction, as any suitable means may be employed-for rotating the valve-stem from the exterior of the Valve-casing.

The front end of the cylindrical valve-plug is provided at its center with a longitudinallyprojecting screw-threaded stud 26, on which is mounted a screw-nut 27, adapted to be held against rotation after proper adjustment through the medium of a pin 28, inserted through the nut into engagement with the screw-stud. The screw-stud and the nut serve to detachably retain in position a valve-face 29, having a diameter co-ordinate with the diameter of the valve-plug.

The material of which the valve-face is composed depends on the purpose for which the shut-off valve is designed. It' the valve isdesigned for the passage of steam, the valveface will be composed of a metallic disk; but if the Valve is designed for air, liquids, or water the valve-face will be composed of rubber, leather, or other suitable Hexible material.

It will be obvious that the screw-stud and nut render it possible to quickly substitute one valve-face for another and to effect repairs in the most economical manner. if a rubber or leather valve-face is employed, it can be easily renewed whenever required. If a ground valve-seat is employed in connection with a metallic valve-face, the seat can be readily reground and the removable and replaceable valve-face easily fitted thereto at very small cost.

The internally-screW-threaded inlet end 2 of the valve-casing is provided with a screwthreaded reducing-plug 30, between which and the rear end of the Valve-plug 14 is arranged a spiral or other suitable spring 3l. The reducing-plug serves to connect with a pipe, and also to vary the tension of the spring, and thereby cause it to press with greater or less force against the valve-plug. The spring aids in seating the valve-plug and holds it tightly against its seat, which is very desirable, particularly Where a low head of water is present or the Huid-pressure is moderately low.

In some instances the front end of the valveplug can be countersunk and a removable and replaceable leather or other flexible valveface placed in the countersunk portion, as will be clearly understood by reference to the modification illustrated by Fig. 4.

The parts are so constructed and relatively arranged that when the valve-plug is moved to its open position the crank 0r eccentric pin 19 is on a dead-center, and when the valveplug is moved to its closed position the crankpin acts as a stop.

The valve illustrated in the modified construction, Fig. 5, is particularly designed for controlling the passage of steam through a steam-pipe. In this form of valve the casing 1a is provided with a straight outlet 3, instead of a curved outlet, as in Fig. 1.

The reducing-plug 30, spring 31, valve-plug 14, longitudinal ribs on the interior of the valve-casing, and guide anges or ribs on the valve-plug are all constructed the same as de. l

scribed with reference to Fig. 1.

The nut 22a is formed with a concaved sea 21L in its lower end, and the iiange or valve 20 is beveled on its upper surface to fit the concaved seat. The upper end of the nut 22a is provided with a packing-nut 32 for pressing a packing 33 against the stem 5, which operates the valve-plug 14.. rlhe angular upper end 25 of the valve-stem 5 is provided with a handle 34, which is indicated by dotted lines. The handle is preferably composed of a wooden sleeve, through which 'a metallic rod passes, andis constructed at one end to engage the angular upper end of the valveoperating stem.

The spring 24a, which corresponds to the spring 24, Fig. 1, is preferably square in crosssection, and a packing-ring 35 is arranged between the upper end of the spring and the ange or valve-collar 20"". The packing and the packing-nut, in connection with the flange or valve-collar 20a, effectually prevent the leakage of steam around thevalve-operating stem.

The referencenumerals in Fig. 5 which correspond with the reference-numerals on Fig. l indicate parts constructed the same as described with reference to Fig. 1, and therefore I do not deem it necessary to again specifically describe the parts vin Fig. 5, which are the same as parts in Fig. 1, and are hereinbefore explained in detail.

Having thus described my invention, what I claim is- 1. The combination of a valve-casing having an inlet 2, an outlet 3, a valve-seat 7, and an upwardly-proj ecting portion 4, a Valve-plug 14 guided in the valve-casing, aspring arranged in rear of the valve-plug and serving to force the same longitudinally against the Valve- IOO lIO

seat, a valve-stem having a flange 20, and a crank or eccentric-pin 19 engaging the valveplug, a nut 22 engaging the upwardly-projecting portion 4, and havinga seat 21 to receive the flange on the valve-stem, and a spring 24 which presses the stem upwardly and forces the flange thereof against the nut,

`substantially as and for the purposes de scribed.

2. The combination of a valve-casing having an inlet 2, an outlet 3, a valve-seat '7, a nut 22, and a plurality of longitudinal ribs 8,

9, and to create longitudinal water passages, a longitudinally-movable,cylindrical valve-plug engagingand guided by one of the.

said longitudinal ribs, a spring arranged in rear of the valve plug and acting to press the same against the valve-seat, a valve-stem having a crank or eccentric-pin 19 engaging the valve-plug, and a ange 2O seated against the nut, and a spring -24 acting to press the valve-stem upwardly and force the flange against the nut, substantially as described.

3. The combination of a valve-casing having an inlet 2, an outlet 3, a valve-seat 7,a nut 22, and an upwardly-proj ectin g portion 4 having a washer 23, a cylindrical valve-plug 14, a rotary valve-stem 5 having a crank or eccentric-pin 19, and a ange'20, a spring 24 acting to press the valve-stem upwardly and force the flange 2O against the nut, a spring 3l arranged in rear of the valve-plug and acting to force the latter against the valve-seat, and a reducer '30 inserted into the inlet end of the valve-casing and bearing against the spring 3l, substantially as and for the purposes described.

4. The combination of a valve-casing having a Valve-seat 7, a cylindrical valve-plug 14 adapted to reciprocate in the valve-casing and provided with a valve-face, a rotary valvestem having-acrank or eccentric-pin for shifting the valve-plug, a spring arranged in rear of the valve-plug and pressing against one end thereof, and an internallyscreW-threaded reducer screwed directly into and adjustable to and vfro in the inlet end of the valve'casing, and bearing against one end of said spring, for varying the tension of the spring and connecting with a pipe.

5. The combination with a valve-casing having a valve-seat '7, and a fixed longitudinal guide-rib 9, of a cylindrical valve-plug 14 having guide-flanges or ribs 15, movable along said fixed rib, a screw-stud 26 carrying a nut 27, a removable and replaceable valve-face 29 supported by the screw-stud and nut, a spring 3l arranged in rear of the valve-plug and acting to force the latter against the' valve-seat, and a reducer 30 screwed directly into, and

adjustable to and fro in the inlet end of the valve'casing and bearing against one end of the said spring, substantially as described.

In testimony whereof I have hereunto set my hand and aiixed my seal in 4presence of two subscribing witnesses.

J OSIAH W. MELVIN. [L. s]

Witnesses:

H. W. NELSON, W. H. MARTIN. 

